1. Field of the Invention
The invention relates to an inspection system for judging the quality of a container made of a flexible material such as paper, and fed with, for example, drink (such as a lactic acid drink) therein, and more particularly, to be capable of facilitating a leaking liquid inspection and an entering air inspection on the same conveyor line at the same time.
2. Description of the Related Art
If liquid such as a lactic acid drink is fed into a container and leaks, various disadvantages will result. For example, a production area becomes unsanitary, facilities for transporting after shipment are contaminated, and further, consumers become dissatisfied when the leaky container is passed to the consumers.
The leaking of the contents is caused by various reasons. For example, the container may have a defect in itself, and/or, there is something wrong in a system for sealing the container after feeding the liquid therein.
In order to prevent the such-disadvantages caused by a liquid leak, the applicant has provided a leaking liquid inspection apparatus for detecting the liquid leak conveniently as disclosed in Japanese Patent Application Disclosure No. 5-124628. According to the aforementioned prior art, detection of a liquid leak can be made automatically, and therefore, automatization of the leaking liquid inspection can be attained. As compared with a manner of inspecting all subjects, since a sampling inspection is utilized, pressure reduction means and/or measuring means can be facilitated in a smaller scale, and/or, elimination (automatic elimination) of an inferior container can be made easier.
On the other hand, if air enters in the container, the amount of liquid fed into such the container is reduced proportionate to the amount of air in the container. As a result, various disadvantages result. For example, when the liquid is a drink, because the amount of drink is less than the regular amount, the consumer may be annoyed.
In order to minimize such disadvantages caused by the aforementioned entering air, the present applicant has provided an entering air inspection apparatus capable of reliably, quickly and automatically detecting air which enters a container when the liquid is fed into the container as disclosed in Japanese Patent Application Disclosure No. 5-124629 (also the container may be flexible). According to such prior art (No. 5-124629), since quality of the container can be judged by detecting the change of a distance between the surface of the container and a fixed point in a closed system accommodation means after and before reducing a pressure, automatization of the entering air inspection can be attained with sufficient accuracy. As compared with a manner of inspecting all subjects, since a sampling inspection is taken place in this prior art, a pressure reduce means and/or a measuring means can be facilitated in smaller scale, and/or, elimination (automatic elimination) of an inferior container can be made easier.
The above-mentioned leaking liquid inspection apparatus and the entering air inspection apparatus which are disclosed (as in Japanese Patent Applications by the applicant) are very effective. At present, however, the above-mentioned two apparatuses are provided as different apparatuses in an inspection area.
However, responding to desires for simplification and space saving of the inspection area, it is desirable that the leaking liquid inspection apparatus and the entering air inspection apparatus are structured to be provided in the same system to simultaneously facilitate the leaking liquid inspection and the entering air inspection.